Spacer-damper for electrical power lines

ABSTRACT

This invention concerns a line conductor spacer including a plurality of spacer arms one for each conductor and preferably formed from one or more stranded cables, relatively movable jaws on each arm to engage and clamp onto its respective conductor, a spacer arm carrying member from which the spacer arms extend, and weight means secured to the arm carrying member for damping movements of the conductors.

United States Patent Bloch et al. 5] Nov. 7, 1972 [54] SPACER-DAMPER FORELECTRICAL [56] References Cited POWER LINES UNITED STATES PATENTS [72]Inventors: Walter Bloch, Leatherhead;

, Christopher Richard, Stevens, 3,443,019 5/1969 Walker et a1. ..174/146X c l b h f England 3,582,983 6/1971 Claren ..l74/ 146 X [73] Assignee:Bowthorpe-l-lellermann Limited Primary Examiner Laramie Askin [22] Fild; J 18, 1971 Attorney-Holcombe, Wetherill & Brisebois This inventionconcerns a line conductor spacer in- [30] Forelgn Apphcatlon Pnomy Datacluding a plurality of spacer arms one for each con- Jan. 21, 1970 GreatBritain ..3,040/70 ductor and preferably fonned from one or morestranded cables, relatively movable jaws on each arm [52] US. Cl..l74/42, 174/146 to engage and clamp onto its respective conductor, a[51] Int. Cl. ..H02g 7/14, H02g 7/12 spacer arm carrying member fromwhich the spacer [58] Field of Search .....l74/4O R, 42, 43, 146, 149 Rarms extend, and weight means secured to the arm carrying member fordamping movements of the conductors.

5 Claims, 3 Drawing Figures SPACER-DAMPER FOR ELECTRICAL POWER LINESThis invention relates to spacers for spacing apart overhe'ad'electricpower lineconductors. y

it is desirable with overhead conductors that not only are they spacedapartbut alsothat provisionshould be made to inhibit movement ofconductors in the subspan between spacer fixing points. a

According to the invention, there is provided a I spacer for spacing aplurality of line conductors, the spacer including a plurality of spacerarms one for each conductor, relatively movable jaws on eacharm toengage and clamp on to its respective conductor, an arm carrying memberfrom which. the spacer arms extend, and weight means secured to the armcarrying member for damping movements of the conductors.

An embodiment .of the invention will now be described by way of exampleonly with reference to the pivot pin 9 about which jaw 8 may be pivoted.A pair of clamping bolts 10 serve to draw the jaws together so that arespective one of four conductors may be clamped. therebetween. Eachhead 6 also includes a pair of parallel bores in each of which isreceived an end of a respective one of a pair of comparatively flexibleelongate members, such as stranded steel cables 13, and an end margin ofa sheath 11 which encases its respective elongate member. and stopsshort of the end of the stranded cable 13-. The sheaths provideprotection of the elongate members from the natural elements and may beselected from materials including polyvinylchloride, cross-linkedpolyethylene, butyl rubber and chlorosulphonated polyethylene. Each headis compressed by for example compression crimping on to the cable andsheath end to secure the head to the elongate memberand also to seal theend of the sheath 1]. Alternatively, thesheath end may'not extend intoits respective bore but may be sealed on to the outer annular surface ofthat portion of the head defining the bore.

At the end of each pair of sheathed members remote from their respectiveheads is a respective one of four bases 12 each having bores forreceiving andengaging the sheathed members in like manner to the head.Each base also includes a semi-cylindrical recess 14 to receive the tube1 and two bores for receiving securing bolts '15.

The bases of two arms are bolted by bolts 15 to diametrically oppositesides of the tube at each end of the tube, 3 and 4 at one end, 2 and 5at the other end, the arms on like sides of the tube (2, 4 and 3, 5)being oppositely directed.

To each end of the tube are secured weights 16 by v bolts 17, theweights serving to dampen any movement of the conductors. The weights 16in association with the flexible elongate members are designed so thatthe I natural resonances of the spacer lie outside thecritical therebyallowing a much better frequency response with respect to damping to beachievedthan has hitherto'been attainable.

The above described spacer can be modified to suit the requirements ofeach individual spacer application. Thus the total weight of the spacermay be adjusted to alter the extentto which the spacer inhibits orbreaks up vertical oscillations of the conductors,1and the anglesubtended by the arms with respect to the longitudinal axis of tube 1may be alteredto vary the sensitivity of the spacer to vertical andhorizontal oscillations of the conductors. The spring rate of theflexible elongate members may also be altered in conjunction with themass and inertia of the weights 16 to vary the overall response of thespacer to conductor movements; further the center to center'spacing ofthe conductor clamping'heads 6 can be altered to allow a spacer suitablefora given conductor size to be arranged to suit a multiplicity ofconductor spacings. v,

Although the above spacer has been described in connection with fourconductors it is clear that the spacer is suitable for spacing two ormore conductors.

In place of tube 1, an elongate thin plate may be used; also, a singleelongate member may be employed inplace of the two elongate-membersdescribed'above for each head 6.

Stops (not shown) may be provided to engage the heads 6 and hence limitthe inward motion of the spacer arms, particularly as a result of ashort circuit on a line conductor; the stops may be positioned in theregion of the weights 16 or may be combined with the weights.

The construction described above provides'a simple robust spacer anddamper.

We claim: a

1. In a spacer-damper for spacing a plurality of substantiallyparalleloverhead electrical line conductors and damping out vibrationstherein, said spacerdamper comprising a plurality of elongate andinextenrange of vibration of the overhead line conductors sible spacerarms, one for 'each conductor, a clamp means on each arm for clampingonto its respective line conductor, and a spacer arm carrying member ofelongate tubular form and comprising an inertial mass'and from which thespacer arms extend, the improvement according to which said membercomprises an inertial mass selected to maintain the natural resonancesof said spacer outside the critical range of vibrations of said lineconductors, and at least one of the spacer arms clamped to two adjacentconductors is resiliently flexible over a substantial portion of itslength transversely to said conductors so as to permit said conductorsto move towards and away from one another against said resilience.

2. A spacer-damper as claimed in claim 1, wherein'a pair of spacer armsextend from opposite sides of the arm carrying member.

, 3. A spacer-damper as claimed in claim 2, wherein the said pair ofspacer arms extend from the arm carry ing member in the same directionrelative to the longitudinal axis of the arm carrying member.

4. A spacer-damper as claimed in claim 2 including two pairs of spacerarms extending in opposite directions relative to the longitudinal axisof the arm carrying member.

5. in a spacer-damper for spacing a plurality of substantially paralleloverhead electrical line conductors and damping out vibrations therein,said spacerdamper comprising a plurality of elongate and inextensiblespacer arms, one for each conductor, a clamp means on each arm forclamping onto its respective line conductor, and a spacer arm carryingmember comprising an inertial mass and from which the spacer arms

1. In a spacer-damper for spacing a plurality of substantially paralleloverhead electrical line conductors and damping out vibrations therein,said spacer-damper comprising a plurality of elongate and inextensiblespacer arms, one for each conductor, a clamp means on each arm forclamping onto its respective line conductor, and a spacer arm carryingmember of elongate tubular form and comprising an inertial mass and fromwhich the spacer arms extend, the improvement according to which saidmember comprises an inertial mass selected to maintain the naturalresonances of said spacer outside the critical range of vibrations ofsaid line conductors, and at least one of the spacer arms clamped to twoadjacent conductors is resiliently flexible over a substantial portionof its length transversely to said conductors so as to permit saidconductors to move towards and away from one another against saidresilience.
 2. A spacer-damper as claimed in claim 1, wherein a pair ofspacer arms extend from opposite sides of the arm carrying member.
 3. Aspacer-damper as claimed in claim 2, wherein the said pair of spacerarms extend from the arm carrying member in the same direction relativeto the longitudinal axis of the arm carrying member.
 4. A spacer-damperas claimed in claim 2 including two pairs of spacer arms extending inopposite directions relative to the longitudinal axis of the armcarrying member.
 5. In a spacer-damper for spacing a plurality ofsubstantially parallel overhead electrical line conductors and dampingout vibrations therein, said spacer-damper comprising a plurality ofelongate and inextensible spacer arms, one for each conductor, a clampmeans on each arm for clamping onto its respective line conductor, and aspacer arm carrying member comprising an inertial mass and from whichthe spacer arms extend, the improvement according to which each spacerarm comprises two flexible stranded-wire cables arranged side-by-sidewith the two cables of at least one of the arms defining a planeparallel to the line conductors so that the arm is more flexible in aplane perpendicular to the line conducTors than in said plane parallelthereto.